Multiple press unit



Oct. 19, 1943. STACY Q 2,332,023

MULQIIPLEYPRESS UNIT Filed April 5, 1940 6 Sheets-Sheet l Jam $52-3 A TTOENEYS Get. 19, 1943. s q

MULTIPLE PRESS UNIT Filed April 5, 1940 6 Sheets-Sheet 2 6 Sheets-Sheet 3 T F. STACY MULTIPLE PRESS UNIT 7 Filed April 5, 1940 L M lww QM n u Oct. 19, 1943.

- //v VENTO/Q ATTOA NQ Oct. 19, 1943. T. l STACY MULTIPLE PRESS UNIT Filed April 5, 1940 6 Sheets-Sheet 4 e W1M \m 0% Oct. 19, 1943. STACY $332,023

' MULTIPLE PRESS UNIT Filed April 5, 1940 6 Sheets-Sheet 5 L 0W PRESSURE PUMP IN l ENTOIP A TTOENEYS Oct. 19, 1943. T. F. STACY 2,332,023

MULTIPLE PRESS UNIT Filed April 5, 1940 6 Sheets-Sheet 6 unit constructed in Patented Oct. 19, 1943 I MULTIPLE PRESS .UNIT

Thomas F. Stacy, Pidua, Ohio, assignor .to;'1he ,French Oil Mill Machinery Company, Biqua,

Applicationlkprilfi, 1940,1 Sei-ial No.i328,059

11 Claims. (o1.' 10o .71)

This invention relates=to' multiple press units and particularly to a unit battery of a plurality of hot plate presses of the side plate type of construction. it 4 An object of the invention is to provide'an improved multiple press unit which is largely selfcontained within: its overall limits, with which there will be a minimum of piping, a maximum capacity within minimum overall dimensions, with which various parts will be easily accessible, and which will be relatively simple, compact,.durable and inexpensive.

Another object of the invention is to provide an improved unit construction for ap urality of side plate presses, which will provide for maximum capacity in a minimum of spacewhich will have all i of the advantagesof accumulator operatedpresses,

with which large pumps and accumulators are unnecessary, which is largely self-containedas to operating-power, andwith 'which all the presses making up the unit are easily accessible fo'ropera embodiment of the invention, and the novelfeaej tures will be particularly pointed outhereinafter in connection with the appended claims.

Intheaccompanying drawings? Fig. 1 is a front elevation of-a multiple press accordance with this inven-.

Fig. 2 is a plan of the same;

Fig. 91s a diagramillustrating the manner in which high pressure operating *fluid i's -automath cally I stored for 'future'use ofthe'. various presses individually, during periods" of -:ina'ctivity of the presses;and' i lr Fig. is a -diagram illustrating the manner ,in

which the different presses arecontrolled from" the sources of low and hi'gh-pressure.

In the illustrated embodiment of thednvention, the improved "unit comprises-a flatg -hollow base ID which serves as a reservoir for -the actuatin fluid. Upon the upper-face -;0i-this baSe :the1varii-' ous presses are arranged in a row; For this-pub pose aflplurality c t-heavy, upstanding plates ll; I2, l3, 14, Hand l'fi tFlgAlare disposedlon end upon the upper face'of the' hollow base -.'l0,' -and' inparallel,--spaced relation tosone another, .the

plates being arranged in a" row salong the base with the planes of theirifaces disposed crosswise of the length of the row.; The adjacentpplates form betweenthem aripluralityuoi chambersjor spaces |1, l8,'3i9, 'and ll...:"Press heads:22 are.

' Fig. 3 is a front elevation, on alargerscalerof a portion of the same, and with-portions thereof H in vertical section to illustrate interior details of construction; 1 i t Fig. 4 is a rear elevation of the unit of Fig. 1;

Fig. 5 is a sectional plan of a portion of the same, with the section taken approximately along theline 5-5 ofFig. 3,; r

Fig. 6 is a transverse sectional elevation through,

the same, thelsection being taken approximately along the line 5-6 of1l='ig.,3;

Fig. 7 isanother transverse; sectionalelevation through the same, but'with the sectiontaken' ap--:

proximately along the line 1-1 of Fig. 37

Fig. 8 is a diagram illustrating the mannerin which low pressure operatingfluid 'isaut'omatie cally stored for future us during periods of inactivity of the difierent presses of the unit;

disposed across the upper partsfof;certainofthese plates in any suitable manner such asiby screws 24 :(Fig. .3) which :passurthrongh ;the.-:end plates [Land [6 and the-intermediate platesgliizendilitinto the adjacent cylinderzheads.v t

Th cylinder heads. adia enttheir uppene ds 0 faces are. provided with ribs i25 along the ides. whicliiare notched into recessesei iinithe ed fifisn faces of the side .Dlates so :as to enga e a nst shoulders :21. 1 on '1' the side DlateS: Similarly; the

press headsllaresecured totheadiacen ates y. s r ws Fis- 3 which pass thr uehthe en walls ,II and "16 into. the press; heads .22 in the end spaces llgand-zl and loy screwsjS .which pass throughjtheeintermediate plate 13 and; I t, defining thespaQe-or chamber-gl9, ;into-- thead jacentpress heads 2:2, flhepresswheadsladjacent their .underfaoes. are providedwithribs 3B which runshorizontalzly al ne..thesid sof. qheads mm frontto roan: andthese ribs arealso notched into:

thezadjacentrfacesof the ,side plates deilning that space or chamber so as to engage agai'nst shoillwdersf3l on the :sidegplates. ,The engesefiientiof the 'ribs 525 and 3.0 with the shouldersjiT-and 3| .respectivelythus resists separatiun. Of; the-pre heads and cylinderiheadsdurine pressins pera tions, the operating stresses beingvltalienmn by' the heavyrside plateszinto w i hth shsedsie mt s flr yftt m amine; i tsrm si t plates [2 and I5 are connected to the adjacent press heads 22 by screws or bolts 32 (Fig. 6) which pass through upstanding flanges on the upper ends of the press heads 22 and through the upper ends of the plates I2 and I5 respectively. The flanges on the press heads which extend along the commonwalls I2 and I5 lie flat against opposite faces of these plates I2 and I5, and are coupled thereagalnst by these screws 32.

Similarly the cylinder heads are coupled to these intermediate walls I2 and I5 by screws or bolts 33 (Figs. 5 and 6). all of the screws or bolts which secure thepress heads and cylinder heads to the side plates of each press are spaced substantially from the ribs 25 and for reasons disclosed in my prior U. S; Patent No. 2,013,587. Each cylinder head is provided with a depending cylinder portion 34 (Fig. 3) and the upper flat face of the reservoir is provided with correspondingly located openings 35 to receive these depending portions 34. This serves to reduce the overall height of the complete unit. .In each cylinder head I mount a ram or piston 35 which reciprocatesvertically toward and from the press head 22 in that chamber or space. A platen 31 is mounted on the outer or upper end of each ram, and the usual heated plates 38 may be disposed ontheplaten, the underface or" the head 22 and also, if desired, at intermediate points between them when the ram is in open position, as usual in the hot plate type of press. These plates-38 are supplied with a heating medium in any suitable manner, but in the particular example shown, steam is supplied through a common supply pipe 39 with a branch leading to each plate 38 that abuts the underface of each press head 22, as shown in Fig. 4. All of these plates '38 in each unit are connected to one anothervertically in. succession by flexible, or

hlngedly connected, pipes 40. arrangedat the rear of each press, and the lowermost plate 38 for each presswhich rests, on the platen 31 is connected by a'fiexible pipe H to a condensation trap 42, there being a condensation trap for each press space. :These condensation or steam traps 42 are connected to discharge to any suitable source through temperature control valves 43' (Fig.4). 3

The plates I3 and I4 which define the central chamber I9, and the end walls II and I5 extend to a greater height than the other intermediate walls I2 and I5, and the upper ends of theintermediate platesl3 and I4 are connected by a rigid frame member 44 (Figs. 3 and 4), this frame member being notched into the upper ends of the plates I3 and I4 and secured therein in any suitable manner such as by the screws 45. .The. frame-member includes as an interior part thereof a dome shaped'section 46 with a downwardly concave face, and a cylinder 4'! is secured to the underface of this dome shaped portion 46 in any suitable manner such as by screws 48. The dome and the cylinder 41 together constitute a major cylinder of a hydro-pneumatic accumulator. The lower end of the cylinder 41 is open and a smaller cylinder 49, having an enlarged head 50 which acts as a piston, reciprocates in the cylinder 41. The smaller cylinder 49 reciprocates over the free upper end of a tubular stem 5| which is secured to and is upstanding froma frame member 52 that extends across between the plates I3 and I4 adjacent their lower ends.

The member 52 is secured, as byscrews 53,.

to bracket members-54.- which are in turn: 7

clamped to the adjacent faces of the plates I3 and I4, as by screws 55. The stem 5| is conveniently secured to the frame member 52 by screws 55. The stem 5| is provided with a passage 51 from end to end thereof and opening downwardly through the frame member 52 and upwardly into the chamber Within the cylinder 49. A pipe 58 opens downwardly through the dome into the interior of the cylinder 41 above the head 50, and this pipe 58 is connected to any source of 7 suitable continuous pressure, such being floated It Will be noted that into a shop airline of any suitable pressure (such as one hundred pounds or more) so that such pressurewill be continuously supplied to the interior of the cylinder 41 above the head 50. This pressure tends to force the piston head 53 downwardly, and such downward movement will in turn force the actuating fluid contained in the interior of the cylinder 49 outwardly through the passage 51. A pipe 53 connects the lower end of the passage 5'Iwith a valve 63 which distributes the displaced actuating fluid selectively and individually to the cylinder heads through pipes 6|, there being an individual pipe 6 I leading from the valve 55: to each cylinder head. The valve 60 is suitably mounted on the frame member 52 such as on beams 52 (Fig. 3).

The valve 63 has a plurality of individual valve mechanisms incorporated in a common valve housing, and also provides for the delivery of actuating fluid under pressure into the cylinder 49 through the passage 5'! at intervals in a manner which will be explained later herein. Also disposed in the chamber I9 between the plates I3 and I4 but preferably below the frame member 52 are a low pressure. pump 63 and a high pressure pump 54. The pumps 63 and 64 may be of any suitable type such as are commonly used in hydraulic press systems. The moving element of the pump 63 is coupled to the shaft 55 of an electric motor 66, so as to be directly and continuously driven thereby, and similarly the high pressure pump 64 is directly coupled to the shaft 61 of an electric motor 68 so that the pump 64 will be directly and continuously driven by the motor 68. The motors 66 and 68 are arranged side by side as shown in Fig. 5 in the chamber IS. The low pressure pump 63 is connected at its intake side by a pipe 69 to the chamber of the base I0 forming the reservoir for the hydraulic system, and similarly the intake side of the high pressure pipe 64 is connected by a pipe 10 to the reservoir in the base. The output side of the low pressure pump 63 is connected by a pipe H to the valve 68, and similarly the output side of the high pressure pump (34 is connected by a pipe 12 to the valve 60.

A low pressure tank or accumulator 73 is disposed above the press heads 22 of the press spaces 20 and 2| (Fig. 3) and across the relatively lower common "plate I5 between those spaces, the tank being supported upon the press heads and the upper edge of l the plate I5. Inasmuch as the plates I4 and I6 extend to a greater that they have a gas chamber in the upper part thereof which is compressed by the injection of liquid under pressure. Inasmuch as the tanks I3 and I4 'act together as a common, low pressure accumulator their upper parts are con livery through the pipe59 to the accumulator 'is'. prevented. The high pressure pump thencir culates the actuating fluid idly back to'the'reservoir in the base I 5, but as soon as the accumu-y lator operates to deliver a high pressure fluidto one of the press cylinders the cylinder '49 (Fig; 3) will fall and carry the arm 54 downwardly, and this will release switch 95 and cause .an opening of the circuit to the solenoid I25; The valve I21 then automatically operates to cut off communication between the pipes 128 and I28 and to vent the pipe l'lilmvhich releases the pressure on the pilot piston I3 I The spring IiIBthen shifts the valve element iIS back into the full line position of Fig. 9, where it closes the port I22 to the Icy-pass and reconnects the pipe" from the high pressure pump to the pipe valve-lassembly'is connected, the pressure fromis built in the cylinder head 23 to which this that cylinderwillbe transmitted to the interior? of thestem I49 was to force the valveelement theland I48 into a position to uncover the high 59 leading to the highpressure accumulator, so

that the pump will then immediately start restoring to the accumulator a high pressure operating fluid. If desired, a choker check valve I34 may be included in the pipe 59 leading to the stem so that when the accumulator is delivering fluid under pressure, the maximum rate at which it can be delivered will be restricte'd by the degree to which the valve I3 4 chokes the flow in that direction. When the flow, however, is

, ably'insertinthe low pressure line I! a ire 'che'ck valve I5I which openst'o' passlow pressure to the port I43aand closes automatically to prevent reverse flow; A pilot valve chamber I52 isipro .vided at the lowerend of each valve chamber I35,

and a pilot piston I53 isgmounted in this pilot.

' cylinde'rorchamber152' formovement by fluid from pipe 59 into the high pressure accumulator. the choker valve automatically swings'to open' position so as to pass the fluid into the accumu lator without material restriction on the rate offlcw.

Referring now to Fig. 10 of the drawings, the valve control for'oneof the press cylinders is illustrated, and it will be understoodthat there is a similar valve arrangement in the main valve 50 for each one of the press'cylinders, connected by a pipe BI to the particular, related press cylinder. For each such valve assembly,- the valve 60 has a valve chamber I and beside it another valve chamber I36. In the chamber I35 is a valve element I31 having spaced lands I33 and I39; A compressionspring Hit-acting between one endof the chamber I35 and the valve element I31 urges the latter into the full line position shown in Fig. 10. The chamber I35 has a port I4I leading to an exhaust'pass'age I42," and another port I43 leading to a correspondingly designated port in the chamber I35. When the valve element I3! is in the full line position shown in Fig. 10, the land I39 covers and closespressure on the full end-of piston I53 in a direc-v tion to move the -valve element I31 against the actionoi the spring I andinto'a position in which the land I38 closes the exhaust port MI and the land" I39 uncovers the port I43. Thezactuating fluid is supplied to the clo-sedend of pilot cylinder or chamber- 152 by'a pipe I54 leading to a' solenoid operated hydraulic valve I551 A pipe I56#leads from the valve I55 to "a suitable source of actuating fluid under pressure, such as to the air lineof thes'hop, and when the valve I55 is operated, itconnec'ts the pipe I56 to the pipe I54, and the fluid passing therethrough op-: erates' the pilot 'piston'l53to shift the valve element-I31 into a position in which land I38 closes the exhaust valve and the land I39 uncoversthe pipeiil leading to the press'cylinder and connects it to the port I43, and thence to=the low the port I43 and the land I33uncovers the-ex the high pressure line 59 from the bypass valve,

and another port |43a connected to the pipe 11; In the chamber !35 is a valveelement I45 which has a land I46 operable when thevalve element is in the full line position in F'igflO, to;

close the high pressure inlet port 154. :Thevalve element I 45also has another land I4'I which,

when in the full line positionof Fig. 10-, uncovers the low pressure inlet port I43a: A spring I48 acts between the wall of the whamber I35 and;-

the land I45 so as to urge the valve element I45 intothe full line position ofv Fig. 10.: The upper land is tubular and reciprocates over. a'stemv I43, into the interior of "which opens a pipe I50 leading from that press cylinder 23 tov which the pipe 6| from the relatedchamber-ISS is connected, so that when a predetermined-" pressurei pressure inlet pipe 11.

When this happens,- fluid under low-pressure flows from pipe 'II tothe pipe BI, and the operation of that particularpress is initiatedu ,When

the pressure in the related cylinder head 23', ask transmitted through/ the pipe I-5Il 'to 'the'lstem I49, is sufiicientto overcome the action of spring uncovers the high pressure inlet portI44, and

the land I4? covers the port I43a. This cuts off the flow of low: pressure at the port I43a a moment after the land I46 uncovers-the high pres-.2

sure inletv port- I44, socthat the high pressure fluid entering from the hydro-pneumatic accumulator through the pipe 59 will pass into the chamber I36, thence through port 143 into-the chamber I35, thence through the chamber I35 andthe pipe'BI thatopens into the chamber I35 between the .ports I 43 and I M. The high pressure fluid islthensupplied to the press cylinder, and :the closingoi the low pressure port I43a prevents the passage, of the high pressure fluid back through i the low pressure-in1et-pipe11, this reverseflow being also prevented by the check valve I 5 I. ,The,

- travel of the press under high pressure then continuesuntil the valve I-is reversed, 1 i

When-the valve I55 is reversed so as to relieve;

the-pressure from th pipe I54 andvent the latter,-. the pilot, piston I53 releases the Valve element I31 and the spring I40 then returns, the

valve element I31 to the full line positiondn Fig, 10 in'which the land I39 closes the inlet port I43 and the land I38 uncovers the exhaust port I4I. This releases the pressure-inthe related press cylinder 23 andthe ram in that cylinder starts to; -descend, .;The valve I55 may-be operated in any I44, leaving port I43 in I suitable manner, one form of control being dis closed and claimed in my copending application Serial No. 297,335 filed September 30, 1939; which provides for a bumping operation of each press, and inasmuch as the details of one control of the valve I55 are covered in said copending application, no reference thereto is made at this time. Instead, a simple circuit is disclosed in which the valve I55 is operated by a core I51 of a solenoid I58 which is connected across line wireslL. and U, with a controlling. switch I59. By closing or opening the switch I59, the valve I55 may be operated. The control of switch I59 may be automatic or manual as desired.

It will be observed that a plurality of side plate presses have been brought together in a comheads disposed each in a space between adjacent plates, a plurality of cylinders each disposed in one of said spaces in which a press head is disposed but spaced from the press head in that pact, self-contained unit with all of the advantages of an accumulator operated press, and with maximum capacity for the relatively, small space occupied by the unit; All of the operating parts are readily available for servicing, and the sevfferal presses of the unit are served by one low pressure pump and one high pressure pump, both relatively small and motor driven. By using the small pumps operating continuously; and storing the energy so developed, all of the advantages of the accumulator system are available in a small compact .unit, and relatively small motors and pumps may be employed. Assembling the side,

plate presses together in this manner makes possible a considerable saving in parts, because many parts are common to several or all of the presses. It will also be observed that the connections for the supply of heat to the various hot plates, and the piping are disposed in the rear, so thatthe press unit is not onlycompact but attractive in appearance. The gauges and control members for each press are also arranged on the front, so as to be in convenient positions for anyone operating any particular press of the unit.

It will be obvious that various changes in the details and arrangement of parts, which have been herein described and illustrated in order to explain the nature of the invention, may be made by those skilled in the art within the principle and scope or the invention, as expressed in the appended claims.

I claim as my invention:

1. A hydraulic press unit, comprising .a base, a plurality of relatively heavy flat plates disposed in upright positions on said base, spaced apart in parallel position across the surface of said base, a press head disposed between and secured to adjacent plates in each of a plurality of the spaces between the spaced plates. a cylinder head also disposed between and secured to adjacent plates in each of the same spaces between plates in which said press heads are disposedbut with the cylinder heads spaced from thepress heads, a

ram mounted in each cylinder head for move ment toward and from the press head in each of said same spaces between adjacent plates, a high pressure accumulator in another one of said spaces which is free or a press ram, motor driven pumping means and controlling valve means also disposed in said another space, a low pressure tank disposed above said press heads between certain of said plates, and connections between said pumping means, valve means, tank and accumulator to form a hydraulic circuit for selective, independent and individual operations of each of aid rams at any time.

2. A hydraulic press unit comprising a base, a

plurality of parallel, upstanding, heavy plates spaced apart along'said base, a plurality of press space, a ram in each cylinder operable toward and from the press head in that same space between Dlates, means for anchoring said press heads and cylinders to the adjacent plates with those plates serving as the stress members connecting the heads and cylinders in each of said spaces in which the press heads are disposed, at high pressure accumulator disposed in another of said spaces which is free of said press rams and tied to and rigidly connecting the plates defining said another space at vertically spaced points in that space, pumping means and valve mean disposed in said another space, and means connecting said cylinders, valve means and pumping means in a hydraulic circuit by which individual and independent operation of each of said rams may be selectively initiated at any time.

3. A hydraulic press unit comprising a base, a plurality of parallel, upstanding, heavy plates spaced apart along said base, a plurality of press heads disposed each in a space between adjacent plates, a plurality of cylinders each disposed in one of said spaces in which a press head is disposed but spaced from the press head in that space, a ram in each cylinder operable toward and from the press head in that same space between plates, means for anchoring said press headsand cylinders to the adjacent plates with those plates serving as the stress members connecting the heads and cylinders in each of said spaces in which the press heads are disposed, a high pressure accumulator disposed in another of said spaces and tied to and rigidly connecting the plates defining said another space at vertically spaced points in that space, pumping means and valve means disposed in said another space, and means connecting said'cylinders, valve means and pumping means in a hydraulic circuit by which individual operation of said rams may be independently and selectively initiated, said base being hollow and connected in said hydraulic circuit to serve as a reservoir therefor.

4. A hydraulic press unit comprising a hollow base having a reservoir for the storage of operating fluid, a plurality of parallel, upstanding heavy plates spaced apart along the top of said base, a plurality of pres heads, each disposed in the upper part of a space between adjacent plates, a plurality of cylinder heads, each disposed in the lower part of a space between adjacent plates in which a press head is disposed, the cylinder heads having dependin cylinders and said base having openings in its top to receive. said depending cyl inders, fastening means connecting said heads to the adjacent plates, with said plates connecting press and cylinder heads to one another in any of said spaces and preventing their separation, aram in each cylinder operable toward and from thepress head in that same space between adjacent plates, means for providing a fluid under pressure disposed in another space between adjacent plates, and an operating hydraulic circuit aeeacas mtermediatepo'sitidns onledges 83 (Figs.

nected together'byjajpipe (Fig: 3): and their lower parts; areconhectedtogether by the pipe 16; enabling the tanks l3 and '14, to act ,tdgether as a common low pressure accumulatorzjy'Ihe pipe 16 is comiected'bya pipe TI to the valve 60,

and throughthevalve 69 it maybe connected K with the pipe-IFH from the low pressure pump' 63. Similarly the pipe 59 leading to the valve 60 from the-passage ,51 of thehigh pressure accu mulator may be connected through theva-lve 60 tothe'pipe l2 leadingfrom the output side of the high pressure pump 64'. The low' pressure pump 63 thus serves to withdraw operating liquidfrom the reservoirin the base) of the unit anddeliver it, when permitted by the valve 60, to thelow pressure tanks 13 and 14 where it is heldunder pressure bythe gas or air in the upper parts of the tanks 13- and 1-4. Similarly thehigh pressurepump ,64 withdraws operating liquidqfrom the reservoir in the base I!) and de-'- livers it;- conti nuously, when permitted by the valve 60, to the cylinder 49 so as to force the latter "upwardly and through the head 50- displace the air from the cylinder 41 into the shop airline through pipe58ir This insures a c0n= tinuous storing of both high and ,loW pressure a-ctuating liquids for delivery in proper sequence to (Figs. 1, 5, 6, 7) except that the plate sections 18 do not cover'those portions of th openings in the press spaces between the press heads and platens as shown in Fig. l, so that except for the openings to the pressing spaces between the platens and press heads, the front of the structure is substantially covered 'by the plate sections 18. The base It] extends rearwardly from the front plates 18 to an extent greater than the upstanding plates II to H5 inclusive, as shown clearly in Figs. 2, 5 and 6, and 'a box-like housing 13 (Fig. 6) is disposed against the rear vertical edge face of the base I0 so as to extend upwardly for a suitable distance such as approximately to the level of the upper ends of the cylinder heads 23 and then forwardly approximately to there'ar edges of the upright plates H to 16 inclusive. This housing 19 is removable and it provides between it and the cylinder heads and the rear edges of the upstanding plates II to I6 inclusive, a chamber in which the piping from the central chamber or space l9 to the difierent cylinder heads may be enclosed. Within the samehousing the pipes 42 from th lowermost of the plates 38, the condensation traps 4-2. and the temperature control valves 43 may also be disposed as well as other auxiliary equipment.

Where elevators are desired for each press, such an elevator may be mounted on a bracket '80 (Fig 6) in any suitable manner such as by screws, 81 which pass through the sides of the bracket and the front plates 18 into the adjacent cylinder I and 3) as usualiii this typecpress;sothat when the platen 31 moves upwardly with iobjectsbeetween .the plates 38, the plates 38* will be picked upin succession and theJentire-igroup' pressed against .;one another and the related press head 22.- When the platen againuis lowered, theintermediate plates 38 .in that press will be lowered until-they engage in succession with-theirrespective lugs 83, and will be supported against further descent at their propenpredetermined positions whilethe other plates 38 andthe platen descend.

p The elevating mechanism may be of any suitable ,type, but in theillustrated example each platform 82 is mounted upon the upper end of a vertically extending screw 84 which is received in a tubular housing 85 depending from the underface of the bracket 8,0 A gear 86 isfixed on a-nut 81 which is disposed above bracket 80 and is threaded uponthe screw or rod}! adjacent its upper end, beneath the platform 82 and a cover 88. The nut abuts atone end face against a shoulder 89 on the upper end of the housing or tube and at its other endface against a shoulder 90 on the underface of thccover 88. Since the nut 81 is thus limited against movement vertically,.. whenever it isrotated it will shift the threadeizl rod}! .endwise in one direction or the other, depending upon the direction of rotation of the nut 81. The, threadedir'od' 334 is (held a ainst rotation but guided for vertical reciprocation by a key 9f carried on the inner face of the time 85 and received in a keyway or slot 91d eXtendihg endwise along the threaded hortiohjof the "roast. The gear at Ines'heswi'th and is driven by apihion '92 carried on the rotor shaftof an,,elec I the ace be weenfthe side flanges of the bracket 80: inan suitable mariner such as by bolting or screwing its base to the depending tube 85.] The motor, "93 is of the reversible type, sothat by its operation. incne direction or the other it win) 7 turn thenuttltin one direction or the other and thussh'ift the'threaded rod 84 vertically inorie direction er the othe'ri't'o' elevate or lower the The cylinder is or the hydrorpnemnatic ac cumulator carries an arm 9'4 --'(Fig. 3) which ex= tends laterallyftherefrom "and below the lower endof the cylinder ll even when the cylinder the arm9'4 will always pursue a definite path in its ascent and descent. A=1imit switch 96 of any. suitable type is disposed in aposition to be operated by the ar'mt lwhen the latter reaches its uppermost, desired-position, and this limit switch Q'Gis ernployedto control 'thefadmission of high pressure actuating fluid to the interior of the cylinder!!! in a manner'which will be "explained hereinafter.

Referring now particularly to Fig. 8, the man ner inwhich-thelow pressure tanks 13 and 14 are supplied continuously with actuating fluid under desired pressure willbe explained. -A portion-bf the valve f 60 connecting pipe 15 and; tank 13 :has a chamber '91, and a valve element 98 is mounted tric'moto'r s3 which'is secured in I I for reciprocationendwise inthat chamber. ;The valve element 98 is provided with spaced lands 99 and I which cover and uncover alternately the ports I0 I- and I02 respectively when the'valve element 98 is shifted endwise. A spring I03, provided in one end of the chamber 91, is under compression and extends into a recess in the adjacent end of the valve element 98, so as to resiliently urge the valve element 98 in one direction (which is downwardly in Fig. 8) to carry the land I00 into the position in which it closes the port I02 and the land 99 into a position in which it uncovers the port MI. The port I02 is connected by a by-pass pipe I04 back to the reservoir, and the port IOI is connected to the pipe 11 which leads to the pipe 16 that connects the tanks 13 and 14. At the bottom of the valve element 60 there is an'auxiliary or pilot chamber I05 which opens upwardly into the chamber 91, and in this pilot chamber I05 I provide apilot piston I06 which has a stem I01 that abuts against the end of the valve element 98 and limits movement of the valve element 98 under the action of the spring I03 beyond that shown in Fig. 8 in which the port I02 is covered and the port IOI is uncovered. The pipe H from the low pressure pump 63 opens into the chamber 91 at a point between the ports IOI and I02, so as to be always in communication with the chamber 91 between the lands 99 and I00.

A pressure responsive switch I08 is connected by pipe I09 to one of the tanks such as tank 13, and when the pressure on the switch I08 exceeds a predetermined pressure for which it is set, it will operate to close a circuit between contacts IIO that are included in series in a line wire L such as by carrying a conducting bridge I II into engagement with the spaced contacts III). The line'wire L after passing the switch contacts H0 is connected to one end of the solenoid II2, the other end of which is connected to the line wire L The solenoid II2 has a core II3 which extends into a valve I I4 that controls the flow of actuating fluid from any suitable source of fluid under pressure, such as an air line connectedto the pipe I I5, selectively to a pipe I I8 which leads to the outer end of the pilot chamber I05. When the pressure responsive switch I08. closes the circuit between contacts H0 and through the solenoid II2, the resulting actuation of the core II 3 will operate the valve II4 to connect the source of fluid under pressure at the pipe II5 to the pipe I I0, and thus admit fluid under pressure to the pilot chamber I05. The pressure in that chamber then forces the piston I05 endwise and shifts the valve element 98 away from its position shown in full lines in Fig. 8 (which will be upwardly in that figure) against the action of spring I03 until the land I00 abuts against the opposite end of the chamber 91, in which position the land I00 uncovers the port I02 and the land 99 covers the port IOI.

When the valve member 98 is in this last mentioned position the pipe H from the pump 63 will be connected directly to the by-pass I04 and cut off from the pipe 11. Then the delivery from the pump 63 will beback to the reservoir idly, with minimum load on the pump 63 and its motor, so long as the pressure in the tank 13 remains up to that predetermined pressure for which the switch I08 is set. When the pressure in tank 13 fallsto a desired extent, th switch I08'will open the circuit through the solenoid II2, whereupon the valve I I4 will be operated in a manner to cut CAD off the flow of compressed fluidfrom the pipe II5 to the pipe H6, and will vent the pipe II6 so that the pressure on the pilot piston I06 will be released, whereupon the spring I03 will then move the valve element 98 back to the position shown in full lines in Fig. 8 where the delivery from the pump is again to the tank 63 until the pressure is again brought up to the desired extent. Thus averysimple arrangement is provided for maintaining a desired pressure in the tanks 13 and 14 with continuous operation of the low pressure pump 63.

Referring now to Fig. 9,'the manner in which the high pressure operating fluid is stored in the hydro-pneumatic accumulator will now be explained. The valve 60is provided with another valve chamber II1 which is separate from the chamber 91, and a valve element H8 is mounted for reciprocation endwise of the chamber H1. The valve element II8 also has spaced lands H9 and I20 which alternately cover and uncover the ports I2I and I22 respectively. The pipe 12 opens into the chamber II1 between the ports I2I and I22 so as always to be placed alternately in communication with the ports I2I and I22 as the valve element II8 is shifted endwise. A spring I23 acts between one end of the chamber H1 and the valve element I I8 so as to resiliently urge the valve element II8 into the position shown in full lines in Fig. 9, in which position the land I20 covers the port I22 and the land II 9 uncovers the port I2I.

In this position of the valve element I I8, the pipe 12 from the high pressure pump is connected to the pipe 59 leading to the stem 5| of the high pressure accumulator, and then through passage 51 thereof (Fig. 3) to the interior of the cylinder 49. The delivery of this fluid forces thecylinder 49 upwardly, and the enlarged head 50on that cylinder 49 also moves upwardly in the cylinder 41 and displaces air or operating fluid from the cylinder 41 above the head 50 into the pipe 58 such as the shop air line. Whenthe cylinder 49 reaches approximately its upper limit of movement, its arm 94 operates the limit switch 96 to complete a circuit by bridging contacts I24 provided in series in the line wire L from any suitable source of current leading to a solenoid I 25, the other side of which solenoid is connected to the line Wire L The solenoid I25 has a core I20 which is connected to the movable valve element of a valve I21 which is similar to the valve II4 of Fig. 8, and which serves to connect a pipe I28 from a suitable sourceof fluid under pressure, such as the shop air line, selectively to a pipe I29 leading to a pilot cylinder I30 provided at the lower end of the chamber II1.

A pilot piston I3I fits the pilot cylinder I30 and has a stem I32 which abuts against the lower end of the valve element II 8 to shift the latter against the action of spring I23, which would be upwardly in Fig. 9. Thus when the limit switch 96 is operated into closed position by the arm 94, the solenoid I25 will operate the valve I21 to connect the pipe I28 from the source of fluid under pressure to the pipe I29, and thus deliver this fluid to the pilot chamber I30 where it operates the piston I3I in a manner to shift the valve element II8 against the action of spring I23 into a position in which the land H9 closes port I2I and the land I20 uncovers the port I22. The valve element I I8 then connects the pipe 12 from the pump to the by-pass pipe I33 leading back to the reservoir in the base I0, and further degreaterheight than the other intermediate plates, mean rigidly connecting together said pair of high intermediate plates adjacent their topv and at a substantial distance below the topin the one space between said high intermediate plates, a hydro-pneumatic accumulator supported by said connecting means in said' one space, press heads disposed between adjacent plates in the others of said spaces, cylinder heads also disposed in the same other spaces, a ram in each. cylinder head operable toward and irorn the press head in that space, said press head's'being each disposed adjacent the tops of the intermediate plates of lesser height, means anchoring said heads to the adjacent plates, a tank disposed above adjacent press heads between said high intermediate plates and and providing between them a. plurality of unit spaces, a presshead and a cylinder headhdisposed in spaced relation to'one'another in each of a number of said spaces, a ram in each cylinder head operable toward and from the press the end plates at each side of said one space,

pipes connectin theupper and lower parts of said tanks, valve means disposed in said one space, a pair of motor driven pumps disposed also in said one space and storing high and low pressure actuating fluids in said accumulator and tanks respectively, and a multiple branch hydraulic circuit having connections including said tanks, said accumulator, said valve means and said pumps, whereby low pressure from said tanks may be admitted to said rams selectively to cause initial movements thereof, and high pressure from, said accumulator admitted to said rams to complete the pressing movements.

6. A hydraulic press unit comprising a hollow base having a reservoir for the storage of operating fluid, a plurality of parallel, upstanding, heavy plates spaced apart along said base on thetop thereof, a spaced press head and a cylinder head with a ram disposed between and coupling two adjacent plates in each of certain of said spaces to provide a plurality of pressing units having common walls between certain of said units, with the ram of each unit operable towards and from the press head in that same space, said cylinder heads having cylinder portions depending into said base reservoir and said hollow base having in its upper wall apertures formed to receive said depending cylinder projections, means disposed in another of said spaces for supplying a source of fluid under high pressure, and a hydraulic circuit including a plurality of branches leading from said one space to said cylinder heads for causing movements of said-rams selectively and individually.

'7. A hydraulic press unit comprising a hollow base, a plurality ,of parallel, upstandingyheavy plates spaced apart along said base on the top thereof, a spaced press head and a cylinder head with a ram disposed between and coupling two adjacent plates in each of certain of said spaces to provide a plurality of pressing units having common walls between certain of said units, with the ram of each unit operable towards and from the press head in that same space, said cylinder heads having depending cylinder portions and said hollow base comprising a reservoir for oper-' ating fluid and having in its'upper wall apertures formed to receive said depending cylinder projections, low pressure accumulator tanks disposed above said press heads and'connected to one another at their tops and bottoms, a hydropneumatic accumulator disposed in another of said spaces, a motor driven, low pressure pump disposed in said another spaceand connected at its intake side to the reservoir formed in said hollow base and at its output side to said tanks,

' ward and from the press head in that space, i

head in that space, said heads being secured to the adjacent plates between which they are dis-' posed to form a plurality of side plate presses, means disposed in another of said spaces for supplying actuating fluid to said cylinder heads individually and selectively, ,and wall means covering the major portion of the front of said spaces but being apertured at the portions of the press spaces between the cylinder and press heads of that space, whereby a compact multiple unit assembly is obtained.

A hydraulic press unit comprising a plurality of upstanding, heavy plates disposed parallel I to one another and spaced apart in a row, with the planes of the faces of said plates extending transversely of the lengthof'the row, a press head and a cylinder head disposed in each of a plurality of spaces defined between adjacent plates, a ram in each cylinder head operable tosaid heads being connected to adjacentplates to unite them into a unit-structure, a source of fluid under pressure disposed in another of said spaces, pipes leading from said another space to each of said cylinder heads and extending along the rear of said unit, plate means covering the frontof said unit, said plate means being apertured between each of said press and cylinder and from a press head, each of said cylinders and 7 heads of each press, and means in said another space for controlling the flow of fluid under pressure from said another space selectively and individually to said cylinder heads through said pipes.

10. A multiple unit hydraulic press of a type which occupies a minimum of floor and room space and has a relatively large capacity, which comprises a hollow base having a reservoir for the storage of press operating fluid, a plurality of parallel, upstanding, heavy plates spaced apart along said base, aplurality of press heads disposed each in a space between a pair of said plates, a plurality of cylinders each disposed in one of'said spaces in which apress head is disposed but spaced therefrom, a ram in each of said cylinders mounted for movement toward press heads being secured to the adjacent heavy 7 spaces free of said rams, cylinders and press a motor driven high pressure pump also disposed heads, a low pressure accumulator tank disposed above a plurality of said spaces and adjacent the press heads therein, and hydraulic circuit means for operating said press rams individually and selectively with fluid under pressure from said hollow base comprising a reservoir for the hy1- draulic operating fluid and having spaced openings in its top wall along said base, a plurality of relatively heavy, parallel, upstanding plates spaced apart along said base between said openings and on opposite sides thereof, with an opening between each pair of adjacent plates, said plates resting atltheir lower edges'on said base, a cylinder head disposed between each pair of adjacent plates of. a plurality of said plates, in adjacent spaces between plates, and coupled to the lower ends of adjacent plates, each head having a closed cylinder end depending into said reservoir through the opening in that space between the adjacent plates and locating said 15 plates against material displacement on said base, a press head above and spaced from each cylinder head and also coupled to the plates between which it extends, a ram in each cylinder head operable by pressure in that head toward the press head above it, and means, including a source of power and controlling mechanism disposed in another space between two of said adjacent plates, forming with said cylinders and reservoir hydraulic circuits by which said rams may be caused to advance and retract selectively and individually by'power from said source under the control of said mechanism.

THOMAS F. STACY. 

